From 2001 to 2011, the rate of single women getting married each year dropped by 22.8 percent, according to The Heritage Foundation's 2014 Index of Culture and Opportunity, released this month. Among the 18- to 33-year-old set, only 26 percent are married, the Pew Research Center reported in March.

Unfortunately, it's not just jewelers and wedding vendors who should be concerned by this trend. ...